[Clinical pharmacokinetics of carboplatin and MCNU in malignant brain tumor and normal brain tissues]

We measured the concentrations of MCNU and CBDCA in the serum, brain tumor and normal brain tissue. Six patients with malignant glioma were treated with intravenous chemotherapy using 80mg/m2 MCNU and 300mg/m2 CBDCA during surgery. After drug administration, specimens of serum, tumor and normal brain tissue were collected every 30 min and then the drug concentration in each sample was measured. The highest MCNU levels in all samples were obtained immediately after administration which followed by gradual decrease. On the contrary, the mean CBDCA levels in the tumor and normal tissue remained almost at a constant level, although serum CBDCA level declined rapidly as MCNU. As expected, MCNU seemed to have advantages in the treatment of brain tumors as it distributed with higher concentration in the tumor tissue than in the serum and normal brain tissue. On the contrary, CBDCA in the tumor tissue did not exceed the concentration in the serum. Nevertheless, it remained longer in the tumor tissue with a constant level, suggesting that CBDCA can achieve an effective area under the concentration versus time curve (AUC) in the brain tumor tissue to kill tumor cells.